When you get that error message try going to the mobile version of the website instead (if it has one). Some sites will automatically detect that you need the mobile version others just show the standard version and you need to manually select the mobile version.
I'm very confused. On the B&N Nook Color page it says it has Flash Player. So why does a pop up always come up to upgrade Flash Player, and when i click it, it will not download it? I thought Flash Player was a big NC selling point? What am I missing here?
Which site are you getting the message from?
I just tried m.crunchyroll.com which played 360p video optimized for mobile just fine, and www.youtube.com which played 240p not optimized for mobile without complaint. (However, getting YouTube down to 240p took some touchscreen target practice.)
Most general websites that have a download an upgraded Flash link are offering a PC download, not a download to an Android device. I've heard at xda-developers that if you have your browser set to PC mode, its telling the website that you have a Mac operating system, so it might be trying to get you to download the latest version of Flash for Mac.
Also, note that Adobe has said they are stopping development work on Mobile Flash, and Mobile Flash version 11 is the last one they are going to do. That Mobile Flash halting further development is not a Nook-specific thing ~ even mighty Sony was caught, since they did not release their PS Vita in time to get an Adobe Flash version developed for the device, so now its left without streaming until they can develop their own HTML5 video streaming support.